Boric Acid and a-D-Xylose

No measurements were carried out with the jS-D-xylose, since it is not known in crystalline form. 

This negative behavior proves, moreover, that during the mutarota- 

With a-lactose the negative influence was less than with the jS-lactose and during the mutarotation reaction the conductivity increased in the case of the former, while it became less in the case of /3-lactose. The two isomers were very carefully purifled. Table VIII gives a review of the measurements.  

There is no doubt that for (8-lactose the conductivity in boric acid increases and for a-lactose it decreases. Thus, in a-lactose two hydroxyls are situated more favorably than in /3-lactose. On the strength of this investigation we may attribute the cis configuration to a-lactose and the trans to the /3-lactose. However, the observations were not accurate enough to serve as a basis for the calculation of a constant for the reversible change of the conductivity at most we can say that this change is of the same order of magnitude as that of the mutarotation. 

Maltose, prepared from starch by treatment with barley malt extract and repeatedly recrystallized from 90 % alcohol, showed the same 

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